



 
Hi Belle, Suppose that $(c,d)$ is the point of tangency of the line $3x  4y + 5 = 0$ and the circle. Since you know the center of the circle if you can find $c$ and $d$ you can write the equation of the circle. I would first write the equation of the tangent line in the form \[y = mx + b\] and from this read off the slope, $m$ of the tangent line. The line segment joining the center of the circle to $(c,d)$ is a radius of the circle and hence this lie is perpendicular to the tangent line. This gives you an equation relating $c$ and $d.$ Do you know another equation relating $c$ and $d?$ Solve the two equations for $c$ and $d.$ Penny  


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